J. Oliver et al., THE SEC61 COMPLEX IS ESSENTIAL FOR THE INSERTION OF PROTEINS INTO THEMEMBRANE OF THE ENDOPLASMIC-RETICULUM, FEBS letters, 362(2), 1995, pp. 126-130
Cross-linking studies have implicated Sec61 alpha as the principal com
ponent adjacent to newly synthesised membrane proteins during insertio
n into the endoplasmic reticulum, Using proteoliposomes which have bee
n reconstituted from purified components of the endoplasmic reticulum
[Gorlich, D and Rapoport, T.A., Cell 75 (1993) 615-630] me have found
that the Sec61 complex, consisting of three subunits, is essential for
the insertion of single-spanning membrane proteins, This is true for
signal-anchor proteins of both orientations, and for proteins with a c
leavable signal sequence, These results support the view that Sec61 al
pha is a major component of the ER translocation site and promotes bot
h the insertion of membrane proteins and the translocation of secretor
y proteins.